There are numerous applications in commerce and industry in which compact, economical, efficient and sealed pressure sensors find utility. For example, U.S. Pat. Nos. 4,728,264 and 4,789,308, and U.S. Application Ser. Nos. 07/324,649 and 07421,810, disclose fuel delivery systems for internal combustion engines in which a pressure sensor is responsive to fuel pressure for modulating application of current to the fuel pump motor. Automotive fuels can be particularly corrosive, and it is therefore important that the pressure sensor access to the fuel line be properly sealed. One can envision numerous other instances in which a fluid pressure sensor must be sealed against leakage--e.g., sensing pressure of environmentally hazardous liquids and gases.
It is therefore a general object of the present invention to provide a pressure sensor that is compact, that is economical to fabricate, that has a minimum number of component parts, and that yields reliable service over an extended operating lifetime Another and more specific object of the invention is to provide a pressure sensor of solid state construction that employs conventional silicon microstructure manufacturing technology.